1. Field of the Invention
The present invention relates to an image encoding device and image decoding device for the purpose of relaying and storing images.
2. Description of the Related Art
When expressing a three-dimensional object on a computer, the conventional method has been to simulate it by inputting information on the shape and surface material of the object into the computer, calculating how it looks. However, in order to express complex shapes and detailed texture, it has been necessary to input large amounts of data, and the scale of the calculations necessary for simulation is enormous.
There is a method known as image-based rendering for expressing three-dimensional objects with a smaller amount of calculation. This involves advance shooting, storing and relaying of images from a large number of viewpoints, which are then displayed in answer to requests (QuickTime VR: Chen S. E. `QuickTime VR: an image-based approach to virtual environment navigation`, SIGGRAPH 1990: 29-38, 1990).
With image-based rendering, images from a large number of viewpoints are shot in advance, so that the amount of data which needs to be stored and relayed is enormous, sometimes exceeding 10,000 images or about 2.4 gigabytes. The problem is, therefore, how to store and relay this data effectively.
In view of this problem which has hitherto existed, it is an object of the present invention to provide an image encoding device whereby a small number of representative images is selected from among the large number of images which are to be stored, relayed, and encoded effectively by using each representative image to express a plurality of images, and by appending their dependent relationships. It is a further object of the present invention to provide a method and a device whereby images are encoded and decoded effectively by virtue of decoding by stages and predicting the next request.